21903219 has 48 divisors (see below), whose sum is σ = 36691200. Its totient is φ = 12477888.

The previous prime is 21903197. The next prime is 21903229. The reversal of 21903219 is 91230912.

It is not a de Polignac number, because 21903219 - 2⁵ = 21903187 is a prime.

It is a super-2 number, since 2×21903219² = 959502005123922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21903192 and 21903201.

It is not an unprimeable number, because it can be changed into a prime (21903229) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 131074 + ... + 131240.

It is an arithmetic number, because the mean of its divisors is an integer number (764400).

Almost surely, 2^21903219 is an apocalyptic number.

21903219 is a deficient number, since it is larger than the sum of its proper divisors (14787981).

21903219 is a wasteful number, since it uses less digits than its factorization.

21903219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 21903219 is about 4680.0874991820. The cubic root of 21903219 is about 279.7924439718.

It can be divided in two parts, 21903 and 219, that added together give a palindrome (22122).

The spelling of 21903219 in words is "twenty-one million, nine hundred three thousand, two hundred nineteen".